Boot from USB/Firewire HD without BIOS support, Fake Signature Method Options

[s4e]

The concept is build a fake HD image, with same signature as external HD. After boot stage1, Windows will match the external HD signature against boot loader information, and think the external HD is the boot disk, and continue boot stage2.

Before start, you need GRUB4DOS, and VMWare, and contig.exe from sysinternals. Here is the detail method:

1. Throw external HD into VMWare as a raw disk, make it USB Boot friendly.
2. Create a 0.1G pre-allocated VMWare image, run contig against the *-flat.vmdk file.
3. Format this VMDK, same filesystem format as external HD.
4. Copy Following file from external HD to VMDK partition:

CODE

\BOOT.INI
\NTDETECT.COM
\NTLDR
\WINDOWS\AppPatch\drvmain.sdb
\WINDOWS\FONTS\svgafix.fon
\WINDOWS\FONTS\svgasys.fon
\WINDOWS\FONTS\vga850.fon
\WINDOWS\FONTS\vgaoem.fon
\WINDOWS\INF\biosinfo.inf
\WINDOWS\system32\bootvid.dll
\WINDOWS\system32\c_1250.nls
\WINDOWS\system32\c_850.nls
\WINDOWS\system32\hal.dll
\WINDOWS\system32\kdcom.dll
\WINDOWS\system32\l_intl.nls
\WINDOWS\system32\ntkrnlpa.exe
\WINDOWS\system32\ntoskrnl.exe
\WINDOWS\system32\config\system
\WINDOWS\system32\drivers\

here 850 is your XP default codepage.
5. Copy first 0x1be bytes of bootsect from external HD to *-flat.vmdk.
6. Change bytes from 0x1b0 - 0x1be, make the VMDK has same MBR checksum as external HD. MBR checksum is sum of 128 ULONG value.
7. Load this VMDK from GRUB4DOS:

CODE

map --read-only (...)/...-flat.vmdk (hd0)
map --hook
rootnotverify (hd0,0)
chainloader +1
boot